As is known, virtually all residential homes utilize electrical power received from a utility company. Typically, utility companies have an excellent record of providing uninterrupted or infrequently interrupted power to their customers at proper voltage levels and line frequency. However, due to the increasing demand for power, power outages have become more frequent. While power outages usually last only for a short duration, an extended power outage may cause more than simple aggravation for customers of the utility. A power outage may render a homeowner's appliances, such as the sump pump, refrigerator or freezer inoperable. If a power outage occurs during a rainstorm, the failure of the sump pump to operate may result in the flooding of the homeowner's basement.
In order to combat these occasional disruptions in service, many residential customers of the utility companies have equipped their homes with stand-by electrical generator systems. These stand-by electrical generator systems include internal combustion engines that drive electrical generators. If the commercial power from the utility company fails, the internal combustion engine of the stand-by electrical generator system is automatically started causing the electrical generator to generate electrical power. When the electrical power generated by the electrical generator reaches the proper voltage and frequency desired by the customer, a transfer mechanism transfers the load imposed by the homeowner from the commercial power lines to the electrical generator.
Typically, the transfer mechanism incorporates switches that isolate the electrical power supplied by the utility company from the generator. In a residential application, the switches are flipped either manually or automatically between the utility source and the generator in order to provide power to the electrical system of the home. These prior art transfer mechanisms often require a homeowner to transfer the entire electrical system of the home onto the generator. Such an arrangement does not provide the homeowner with the ability to decide which circuits of the home's electrical system are to be powered. It can be appreciated that the demands of the entire electrical system of the home can be quite significant. As a result, the generator must be of sufficient size to power the entire electrical system of the home. This, in turn, increases the overall cost of the stand-by electrical generator system for the homeowner.
Therefore, it is a primary object and feature of the present invention to provide a transfer switch that transfers the electrical power supplied to essential devices within a residential home between a utility source and stand-by electrical generator.
It is a further object and feature of the present invention to provide a transfer switch that automatically transfers the electrical power supplied to essential devices within a residential home from a utility source to a stand-by electrical generator in response to a power outage.
It is a still further object and feature of the present invention to provide a transfer switch for transferring the electrical power supplied to essential devices within a residential home between a utility source and a stand-by electrical generator that may be simply and easily installed.
In accordance with the present invention, a transfer switch is provided. The transfer switch transfers the supply of electrical power to a load between a utility source and a generator that generates electrical power when started. The load is interconnected to the utility source through a first circuit breaker and to the generator through a second circuit breaker. Each circuit breaker is movable between an on position and an off position. The transfer switch includes a first arm movable between a first position and a second position wherein the first arm is engageable with the first circuit breaker for moving the first circuit breaker from the off position to the on position. A second arm is movable between a first position and a second position engageable with the second circuit breaker for moving the second circuit breaker from the off position to the on position. A control structure selectively urges the first and second arms to the second positions.
A bar extends between the first and second circuit breakers. The bar moves the second circuit breaker to the off position when the first circuit breaker moves to the on position and moves the first circuit breaker to the off position when the second circuit breaker moves to the on position.
The control structure includes a rotatable arm selectively engageable with one of the first and second arms to move the one of the first and second arms to the second position. The rotatable arm is also axially movable between a retracted position and an extended position. The control structure includes a biasing structure for urging the rotating arm towards the extended position. The rotating arm includes a terminal end and a bearing rotatably mounted to the terminal end of the rotating arm. The bearing is engageable with the first and second arms. The control structure also includes a motor operatively connected to the rotatable arm for rotating the arm and a controller operatively connected to the generator. The controller actuates the motor in response to a command from the generator. The controller also includes first and second switches movable between off positions and on positions. The positions of the switches control actuation of the motor.
The control structure further includes a cam disk disposed between the rotating arm and the first and second switches. The cam disk has a first camming surface engageable with the first switch for actuating the first switch and a second camming surface engageable with the second switch for actuating the second switch.
In accordance with a further aspect of the present invention, a transfer switch is provided for transferring the supply of electrical power to a load between a utility source and a generator that generates electrical power when started. The load is interconnected to the utility source through a first circuit breaker and to the generator through a second circuit breaker. Each circuit breaker is movable between an on position and an off position. The transfer switch includes a first arm movable between a first position and a second position wherein the first arm is engageable with the first circuit breaker for moving the first circuit breaker from the off position to the on position. A second arm is movable between a first position and a second position engageable with the second circuit breaker for moving the second circuit breaker from the off position to the on position. A bar extends between the first and second circuit breakers. The bar moves the second circuit breaker to the off position when the first circuit breaker moves to the on position and moves the first circuit breaker to the off position when the second circuit breaker moves to the on position.
A rotatable arm is selectively engageable with one of the first and second arms to move the one of the first and second arms to the second position. In addition, the rotatable arm is axially movable between a retracted position and an extended position. A biasing structure urges the rotatable arm towards the extended position. The terminal end of the rotatable arm includes a bearing rotatably mounted thereto. The bearing is engageable with the first and second arms.
A motor is operatively connected to the rotatable arm for rotating arm and a controller is operatively connected to the generator. The controller actuates the motor in response to a command from the generator. The controller includes first and second switches movable between off positions and on positions. The positions of the switches control actuate the motor. A cam disk is disposed between the rotatable arm and the first and second switches. The cam disk includes a first camming surface engageable with the first switch for actuating the first switch and a second camming surface engageable with the second switch for actuating the second switch.
In accordance with a still further aspect of the present invention, a transfer switch is provided for transferring the supply of electrical power to a load between a utility source and a generator that generates electrical power when started. The load is interconnected to the utility source through a first circuit breaker and to the generator through a second circuit breaker. Each circuit breaker is movable between an on position and an off position. The transfer switch includes a first arm movable between a first position and a second position wherein the first arm is engageable with the first circuit breaker for moving the first circuit breaker from the off position to the on position. A second arm is movable between a first position and a second position engageable with the second circuit breaker for moving the second circuit breaker from the off position to the on position. A rotatable arm selectively engages one of the first and second arms to move the one of the first and second arms to the second position. A motor is operatively connected to rotatable arm for rotating the arm. A motor control is operatively connected to the motor for actuating the motor and an actuation element is operatively connected to the rotatable arm. The actuation element communicates with the motor control for controlling actuation of the motor.
A bar extends between the first and second circuit breakers. The bar moves the second circuit breaker to the off position when the first circuit breaker moves to the on position and moves the first circuit breaker to the off position when the second circuit breaker moves to the on position. The rotating arm is axially movable between a retracted position and an extended position. A biasing structure urges the rotating arm towards the extended position. The rotating arm also includes a terminal end and a bearing rotatably mounted to the terminal end of the rotating arm. The bearing is engageable with the first and second arms. First and second switches are operatively connected to the motor control and are movable between off positions and on positions. The positions of the switches control actuation of the motor. The actuation element includes at least one camming surface engageable with at least one switch for moving the at least one switch between the off position and the on position.